Oil collection system and method for deepwater spills

ABSTRACT

A subsea spill containment system comprising: a funnel structure positioned over a subsea leak; a plurality of interconnected skirts serially joined above the funnel; a collection dome above the skirts; and a hose connected to the dome. The skirts may be supported by one or more central internal longitudinal supports, such a drillpipe or solid rods. There may be multiple supports and/or multiple skirts per support. The skirts are preferably sealed to the dome, the funnel, and each other. The system may be held in place over the leak using cables secured to two or more anchor points, such as suction piles. The system may be moved aside by manipulating the cables, thereby providing access to the leak.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a non-provisional application of, and claimspriority benefit to, U.S. Patent application Ser. No. 61/385,223, filedSep. 22, 2010, and U.S. Patent application Ser. No. 61/416,520, filedNov. 23, 2010, both of which are incorporated herein by specificreference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO APPENDIX

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The inventions disclosed and taught herein relate generally to offshoreoil field tools; and more specifically relate to systems and methods forcollecting oil from deepwater spills.

2. Description of the Related Art

Known systems and methods for dealing with a sub-surface leak or spillinvolve efforts to contain and skim spilled oil at the surface and/orthe use of dispersants.

The inventions disclosed and taught herein are directed to an improvedsystem and method for capturing the oil before it gets to the surface.

BRIEF SUMMARY OF THE INVENTION

A subsea spill containment system comprising: a funnel structurepositioned over a subsea leak; a plurality of interconnected skirtsserially joined above the funnel; a collection dome above the skirts;and a hose connected to the dome. The skirts may be supported by one ormore central internal longitudinal supports, such a drillpipe or solidrods. There may be multiple supports and/or multiple skirts per support.The skirts are preferably sealed to the dome, the funnel, and eachother. The system may be held in place over the leak using cablessecured to two or more anchor points, such as suction piles. The systemmay be moved aside by manipulating the cables, thereby providing accessto the leak.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 illustrates a particular embodiment of a deepwater oil spillcollection system utilizing certain aspects of the present inventions;

FIG. 2 illustrates alternative embodiments of a deepwater oil spillcollection system utilizing certain aspects of the present inventions;and

FIG. 3 illustrates an alternative embodiment of a deepwater oil spillcollection system utilizing certain aspects of the present inventions.

DETAILED DESCRIPTION OF THE INVENTION

The Figures described above and the written description of specificstructures and functions below are not presented to limit the scope ofwhat Applicants have invented or the scope of the appended claims.Rather, the Figures and written description are provided to teach anyperson skilled in the art to make and use the inventions for whichpatent protection is sought. Those skilled in the art will appreciatethat not all features of a commercial embodiment of the inventions aredescribed or shown for the sake of clarity and understanding. Persons ofskill in this art will also appreciate that the development of an actualcommercial embodiment incorporating aspects of the present inventionswill require numerous implementation-specific decisions to achieve thedeveloper's ultimate goal for the commercial embodiment. Suchimplementation-specific decisions may include, and likely are notlimited to, compliance with system-related, business-related,government-related and other constraints, which may vary by specificimplementation, location and from time to time. While a developer'sefforts might be complex and time-consuming in an absolute sense, suchefforts would be, nevertheless, a routine undertaking for those of skillin this art having benefit of this disclosure. It must be understoodthat the inventions disclosed and taught herein are susceptible tonumerous and various modifications and alternative forms. Lastly, theuse of a singular term, such as, but not limited to, “a,” is notintended as limiting of the number of items. Also, the use of relationalterms, such as, but not limited to, “top,” “bottom,” “left,” “right,”“upper,” “lower,” “down,” “up,” “side,” and the like are used in thewritten description for clarity in specific reference to the Figures andare not intended to limit the scope of the invention or the appendedclaims.

Applicants have created a subsea spill containment system comprising: afunnel structure positioned over a subsea leak; a plurality ofinterconnected skirts serially joined above the funnel; a collectiondome above the skirts; and a hose connected to the dome. The skirts maybe supported by one or more central internal longitudinal supports, sucha drillpipe or solid rods. There may be multiple supports and/ormultiple skirts per support. The skirts are preferably sealed to thedome, the funnel, and each other. The system may be held in place overthe leak using cables secured to two or more anchor points, such assuction piles. The system may be moved aside by manipulating the cables,thereby providing access to the leak.

FIG. 1 is an illustration of a particular embodiment of a deepwater oilspill collection system utilizing certain aspects of the presentinventions. The system includes a plurality of interior longitudinalsupports and a plurality of skirts surrounding the supports. Theinterior longitudinal supports may be commonly available steel drillpipe in high strength steel. In this case, the interior longitudinalsupports may be approximately forty feet in length and two and threeeights, two and seven eights, three, three and a half, four, or four anda half inches in outside diameter. Of course, larger drill pipe may beused, but it is anticipated that smaller, lighter pipe will be morebeneficial as the additional strength is not anticipated to typically benecessary.

Alternatively, the interior longitudinal supports may be purpose built,or otherwise differ from commonly available drill pipe. For example, theinterior longitudinal supports may be twenty, thirty, forty, fifty feetin length, or fall into some range therein, such as between twenty andforty feet, between thirty and forty feet, between twenty five and fortyfive feet, or between thirty five and forty five feet.

The interior longitudinal supports may also be solid or partially solid,as the system of the present invention does not necessarily require themto be hollow thoughout, like commonly available drill pipe. Furthermore,interior longitudinal supports do not necessarily need to be steel.Rather, the interior longitudinal supports may be made of aluminum, analuminum alloy, or even a composite material, such as fiberglass, carbonfiber, or plastic material.

In any case, the interior longitudinal supports preferably connect withone another using treaded connections typically found on commonlyavailable drill pipe. Therefore, workers on a rig, drillship or otherinstalling vessel will be accustomed to assembling the system of thepresent invention and may do so using equipment and techniques normallyused in offshore drilling environments. The system may utilize one, two,three, four or more of the interior longitudinal supports, or mayutilize a number falling within a range thereof, such as between two andfour or between three and five of the interior longitudinal supports.

The skirts of the present invention are preferably constructed of aflexible, yet strong fabric and are designed to contain and funnel oilfrom the spill or leak up toward the surface. For example, in someembodiments, the skirts may be cylindrical, segmented cylindrical,conical, and/or segmented conical in shape, with a bottom portion of anupper skirt forming a seal with an upper portion of a lower skirt.Alternatively, the skirts may be rigid and/or reinforced. For example,the skirts may be made of aluminum, an aluminum alloy, or even acomposite material, such as fiberglass, carbon fiber, or plasticmaterial.

There may be one, two, three, four, five, six, seven, or eight skirtsattached to each support, or may vary according or some range thereof,such as four or five, three to six, or two to seven skirts per support.Thus, the skirts may be five, ten, fifteen, twenty, or even forty feetin length, or fall into some range therein, such as between five and tenfeet, between five and fifteen feet, between five and twenty feet,between ten and fifteen feet, between ten and twenty feet, between tenand forty feet, between fifteen and twenty feet, or between fifteen andforty feet.

The skirts may be one, two, three, four, five, six, seven, eight, nine,ten, twelve, fifteen, or even twenty feet in diameter, and may be sizedaccording to the capability of an installing drillship and/or the flowcapacity of the leak or reservoir. Of course, the skirts may be designedto accommodate a range of situations, and may therefore be fall intosome range therein, such as between three and five feet, between two andseven feet, between three and eight feet in diameter, or between ten andtwenty feet in diameter. Additionally, the skirts' diameter may varyalong their length, such that skirt is narrower at the top portion asopposed to the bottom portion. This variance in diameter may be gradual,relatively continuous, or may be localized to an area near the top orbottom of the skirt. In this manner, a bottom portion of an upper skirtforming a seal around the outside of an upper portion of a lower skirt.This seal may be a simple press-fit seal and/or may be an expanding sealoperated by pneumatics and/or hydraulics.

The skirts may be attached to the supports by a cylindrical and/orconical frame. The frame may be made of steel, aluminum, an aluminumalloy, or even a composite material, such as fiberglass, carbon fiber,or plastic material. The frame may also include a plurality of hoops, orrings, to support the skirt. The frame may also include sealing rings,such as on an upper and/or lower most one of the supporting hoops, to afacilitate the seal between upper and lower skirts. The frame may attachto the interior longitudinal supports near the top of each skirt, thebottom of each skirt, and/or at one or more places along the length ofeach skirt. Thus, the frame may rigidly secure the skirt to thelongitudinal supports, or may allow the skirt to sway relative to thesupports.

The frame may be welded directly to the interior longitudinal supportsand/or may be secured thereto using J-Lay collars, or similar structure.Thus, the frames and skirts may hang, or be suspended, from the top, orbottom, of a flange near a connection of the interior longitudinalsupports. Where the frames hand from the supports, a bottom most ring ispreferable made weighted, such as by being made of steel, to weight downthe skirt and ensure each skirt seals with a lower skirt.

Because the system may use multiple skirts mounted on each of multiplesupports, the system may include between two and thirty skirts, betweenfive and twenty skirts, between five and thirty skirts, between ten andtwenty skirts, or between ten and thirty skirts, such as ten, fifteen,twenty, or thirty skirts. In one embodiment, the system utilizesnineteen skirts suspended on four supports.

At the top of the upper most skirt, the system preferably includes adome, or collection structure with a hose attachment collar. The domemay be constructed of steel, aluminum, an aluminum alloy, or even acomposite material, such as fiberglass, carbon fiber, or plasticmaterial. The dome may also be supported by a frame, if needed. The hoseconnects the dome with a collection ship, the rig, drillship or otherinstalling vessel in order to direct the oil collected by the system tothe surface in a controlled manner. Similar to the skirts, the dome, orits frame, may be welded to the support and or may be secured to aflange or J-lay collar.

The flexible segmented nature of the skirts allow them to be installedon the support after it has been threaded, or welded, to a lower supportand/or a j-lay collar between adjacent supports. In any case, thesupports preferably carry the weight of the skirts. Also, a bottom rigidframe may provide a tensioning mechanism for the skirts and/or a basefor a packer and/or Chevron type seal. The seal system will allow eachskirt to use the surface of a lower support top ring as bearing surfaceto reduce or eliminate the amount of water intake from outside.

The system also preferably includes a funnel structure at the bottom ofthe lower most skirt to collect the oil. The lower, larger outerdiameter of the funnel may be between five and twenty feet across, suchas six feet, eight feet, ten feet, twelve feet, sixteen feet, eighteenfeet, twenty feet, or even twenty-five feet in diameter. In someembodiments, the larger outer diameter of the funnel may besignificantly larger, such as between thirty and forty feet across.

If the above described components of the system, as constructed areheavier than the surrounding seawater, the system may include one ormore air cans, or floats to suspend the system. For example, asdescribed, the supports, skirts, frame, and/or dome may be constructedof steel, which would tend to sink. The air cans are preferably sizedand configured to prevent this. Thus, there may be between two and tenair cans, such as four, six, or eight. The system may be configured withtwo or three times as many air cans as needed to provide a level ofredundancy.

The system is preferably secured to the seabed using two or more suctionpiles around the spill location, or source. The funnel, lower mostsupport, and/or lower most skirt and/or frame may be secured to thesuction piles with one or more lengths of wire, cable, chain, rope, orthe like. The length of the wire between the suction piles and the aboveassembly can be modified to raise and lower the funnel and/or move theassembly to the side in the event direct intervention to the spillsource is needed. If a cap can be installed on the spill source; thenflow from the cap can be channeled into the above system, or directly tothe hose and surface vessel. The system thus advantageously allowsaccess to the well, or spill source. The system may also be configuredto handle above and underground blow outs and can be placed anywhere oilis leaking.

With the surface vessel drawing collected oil and/or water from the domeat the top of the system, and/or through the interior longitudinalsupport, a pressure differential is created, thereby drawing the leakingoil into the system. In other words, the system collects oil via apressure differential from the vessel taking the oil from top of thedome. The density difference between oil and water is alsoadvantageously utilized to draw oil up into the system. The surfacevessel may also inject a liquid or gas, such as air, through theinterior longitudinal supports to be vented through holes in theinterior longitudinal supports at selected depths along the system toreduce the density of the liquid within the system, thereby assistingand/or facilitating drawing the oil and/or other liquids into andthrough the system. In the event the surface vessel needs to disconnectthe hose, the system will vent through the hose from the top and thefunnel from the bottom so the system does not necessarily experience anypressure build up. When the hose is disconnected it may drop and hangbeside the skirts of the system.

FIGS. 2 and 3 illustrate another construction for the skirts. While thisconstruction for the skirts may be similar to that discussed above,rather than being constructed of a flexible fabric, the skirts may berigid. For example, the skirts may be constructed from steel, alightweight rigid composite, and/or alloy pipe. This pipe may bethreaded at each end, thereby allowing joints to be made for the skirtsmuch like the interior longitudinal supports and/or commonly availabledrill pipe. Joints between rigid skirts may or may not include the pressfit and/or expanding seal discussed above. In this embodiment, theskirts are expected to be generally cylindrical, with an expanded end.For example, the skirts may have an expanded lower end that slips over,or threads onto, an upper end of a lower skirt. Alternatively, theskirts may be generally cylindrical, with a reduced diameter end. Forexample, the skirts may have an reduced diameter upper end that slipswithin, or threads into, lower end of an upper skirt. Of course, theopposite construction is possible as well, such that the skirts have anexpanded upper end and/or a reduced diameter lower end. While theexpanded end and/or reduced diameter end may be integral to the skirts,such expanded ends and/or reduced diameter ends may be formed with oneor more sleeves or collars secured to an exterior or interior of theskirts.

In the embodiment shown in FIGS. 2 and 3, the skirts are expected to beapproximately forty feet in length and approximately twenty feet indiameter, but may fall within some range. For example, the skirts may bebetween five and ten feet, between five and fifteen feet, between fiveand twenty feet, between ten and fifteen feet, between ten and twentyfeet, between ten and thirty feet, between fifteen and twenty feet, orbetween fifteen and thirty feet in diameter. The skirts for thisembodiment, may or may not utilize the frame discussed above, and/or maybe secured directly to the interior longitudinal supports using J-Laycollars, or similar structure. Thus, the skirts may be longer continuousrigid segments, such as with one large skirt to each interiorlongitudinal support, as opposed to the multiple smaller flexible skirtsto each interior longitudinal support described above. Of course,depending on the application, any combination of these features may beutilized.

The skirts made be pre-assembled upon the interior longitudinal supportsawaiting installation above the spill. For example, where the skirts arerigid, one interior longitudinal support, or skirt, may be pushed,pressed, raised, or lowered toward another until the joint between thetwo adjacent interior longitudinal supports is made and then theexpanded end of one skirt may be slid, or threaded, over the otherskirt. The seal between the two skirts may then be activated,pneumatically and/or hydraulically, through a port in the expanded endof the skirt. Flexibility in the frame and/or other components mountingthe skirts to the interior longitudinal supports may allow access to thejoint between the two adjacent interior longitudinal supports before theseal between the two adjacent skirts has been achieved. This process maybe repeated until the system, of the desired size, length, or depth, isassembled over the spill.

Other and further embodiments utilizing one or more aspects of theinventions described above can be devised without departing from thespirit of Applicant's invention. For example, one or more of theinterior longitudinal supports may be hollow and/or may have holesbetween the exterior and any interior spaces. In this case, andespecially where the surface vessel draws collected oil and/or waterthrough the interior longitudinal support, the holes may be located inorder to draw oil and/or water at a selected depth, or height within thesystem. Alternatively, as discussed above, these holes may be utilizedto inject liquid or gas between the interior longitudinal supports andthe skirts selected depths, or heights within the system. This willallow the system to control the density difference along the watercolumn, and/or prevent the oil and/or water to density from gettingconcentrated and/or eliminated. More specifically, as different hollowregions take oil from the confined space within the skirts, the systemmay also allow water to come in a gap between the skirts and maintaincertain level of density difference throughout the column. Taking oilfrom the confined space within the skirts may allow the system tocontrol a speed at which the spilled oil rises toward the surface.Additionally, or alternatively, as discussed above, the system mayinject liquid or gas into the confined space within the skirts, tofurther control the density and/or the speed at which the spilled oilrises toward the surface.

Finally, this arrangement could be used for power generation, such as byusing density difference in the ocean due to temperature differencebetween deep and shallow water and/or the density difference generatedby oil in the water column as described above, with a turbine orturbines at different locations. These turbines could also be used tocontrol the flow of oil and/or water within the system.

The various methods and embodiments of the present invention can beincluded in combination with each other to produce variations of thedisclosed methods and embodiments. For example, multiple strings ofskirts may be used with one funnel and/or multiple systems may be usedin close proximity to cover a large area spill. Discussion of singularelements can include plural elements and vice-versa. Further, the orderof steps can occur in a variety of sequences unless otherwisespecifically limited. The various steps described herein can be combinedwith other steps, interlineated with the stated steps, and/or split intomultiple steps. Similarly, elements have been described functionally andcan be embodied as separate components or can be combined intocomponents having multiple functions.

The inventions have been described in the context of preferred and otherembodiments and not every embodiment of the invention has beendescribed. Obvious modifications and alterations to the describedembodiments are available to those of ordinary skill in the art. Thedisclosed and undisclosed embodiments are not intended to limit orrestrict the scope or applicability of the invention conceived of by theApplicants, but rather, in conformity with the patent laws, Applicantsintend to fully protect all such modifications and improvements thatcome within the scope or range of equivalent of the following claims.

1. A subsea spill containment system comprising: a funnel structurepositioned over a subsea leak; a plurality of interconnected skirtsserially joined above the funnel; a collection dome above the skirts;and a hose connected to the dome.
 2. The system as set forth in claim 1,wherein the skirts are supported by one or more central internallongitudinal supports.
 3. The system as set forth in claim 2, whereinthe supports are metal pipes at least twenty feet in length.
 4. Thesystem as set forth in claim 2, wherein the supports are solid rods atleast twenty feet in length.
 5. The system as set forth in claim 2,wherein there are at least four skirts secured to each support.
 6. Thesystem as set forth in claim 1, wherein an upper most one of the skirtsis sealed to the dome.
 7. The system as set forth in claim 1, wherein alower one of the skirts seals to an upper one of the skirts.
 8. Thesystem as set forth in claim 1, wherein a lower most one of the skirtsseals to the funnel.
 9. The system as set forth in claim 1, furtherincluding at least two anchor points secured to a seabed around the leakand cables connecting the anchor points to the funnel, the skirts, aframe or other support of the system to hold the funnel over the leak.10. The system as set forth in claim 1, wherein the cables areconfigured to be manipulated to move the funnel relative to the leak.11. A method for containing a subsea spill, the method comprising thesteps of: positioning a funnel above a subsea leak; positioning a firstskirt above the funnel; positioning a second skirt above the firstskirt; positioning a collection dome above the skirts; connecting a hoseto the dome; and drawing oil from the dome through the hose.
 12. Themethod as set forth in claim 1, further comprising supporting the skirtswith one or more central internal longitudinal supports.
 13. The methodas set forth in claim 12, wherein the supports are metal pipes at leasttwenty feet in length.
 14. The method as set forth in claim 12, whereinthe supports are solid rods at least twenty feet in length.
 15. Themethod as set forth in claim 12, wherein there are at least four skirtssecured to each support.
 16. The method as set forth in claim 11,further comprising sealing the second skirt to the dome.
 17. The methodas set forth in claim 11, further comprising sealing the first skirt tothe second skirt.
 18. The method as set forth in claim 11, furthercomprising sealing the first skirt to the funnel.
 19. The method as setforth in claim 11, further comprising setting at least two anchor pointsinto a seabed around the leak and securing the funnel, the skirts, aframe or other support with cables connected to the anchor points,thereby holding the funnel over the leak.
 20. The method as set forth inclaim 11, further comprising manipulating the cables to move the funnelrelative to the leak.